<template>
  <view>
    <my-search @click="gotoSearch()"></my-search>
    <view class="scroll-view-container">
      <!-- 菜单 -->
      <scroll-view scroll-y="true" :style="{height:wh+'px'}" class="left-scroll-view">
        <block v-for="(item,i) in cateList" :key="item.cat_id">
          <view :class="['left-scroll-view-item',i===active?'active':'']" @click="activeChanged(i)">{{item.cat_name}}
          </view>
        </block>
      </scroll-view>
      <!-- 详情 -->
      <scroll-view scroll-y="true" :style="{height:wh+'px'}" class="right-scroll-view" :scroll-top="scrollTop">
        <!-- 种类 -->
        <view v-for="(item1,i1) in cateLevel2" :key="item1.cat_id">
          <!-- 标题 -->
          <view class="cate-lv2-title">
            /{{item1.cat_name}}/
          </view>
          <!-- 品牌 -->
          <view class="cate-lv3-list">
            <view class="cate-lv3-item" v-for="(item2,i2) in item1.children" :key="item2.cat_id"
              @click="gotoGoodsList(item2)">
              <image :src="item2.cat_icon.replace('dev', 'web')" mode=""></image>
              <text>{{item2.cat_name}}</text>
            </view>
          </view>
        </view>
      </scroll-view>
    </view>
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  export default {
    mixins: [badgeMix], // 延续引入组件的定义域至当前页面
    data() {
      return {
        // 可用高度
        wh: 0,
        cateList: [], // 菜单
        active: 0,
        cateLevel2: [], // 详情
        scrollTop: 0
      };
    },
    onLoad() {
      const sysInfo = uni.getSystemInfoSync()
      this.wh = sysInfo.windowHeight - 50 // 搜索框高度
      this.getCateList()
    },
    methods: {
      async getCateList() {
        const {
          data
        } = await uni.$http.get('/api/public/v1/categories')
        // 请求失败
        if (data.meta.status !== 200) return uni.$showMsg()
        // 成功
        this.cateList = data.message
        // 给每个品牌挂载url属性作为正确的图片地址 已用行内方法替代
        // data.message.forEach(item => { // cateList
        //   item.children.forEach(item1 => { // cateLevel2
        //     item1.children && item1.children.forEach(item2 => {
        //       item2.url = item2.cat_icon.replace('dev', 'web') // 字符串替换
        //     })
        //   })
        // })
        this.cateLevel2 = data.message[0].children
      },
      // 切换菜单
      activeChanged(i) {
        this.active = i
        this.cateLevel2 = this.cateList[i].children
        // 规避惰性bug
        this.scrollTop = this.scrollTop === 0 ? 1 : 0
      },
      // 点击品牌
      gotoGoodsList(item) {
        uni.navigateTo({
          url: '/subpkg/goods_list/goods_list?cid=' + item.cat_id
        })
      },
      // 点击搜索
      gotoSearch() {
        uni.navigateTo({
          url: '/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
  .scroll-view-container {
    display: flex;
    background-color: #ffffff;

    // 左侧
    .left-scroll-view {
      width: 120px;

      .left-scroll-view-item {
        background-color: #f7f7f7;
        line-height: 60px;
        text-align: center;
        font-size: 12px;

        // 并且如果有active类名的话
        &.active {
          background-color: #ffffff;
          position: relative;

          &::before {
            content: ' ';
            display: block;
            width: 3px;
            height: 30px;
            background-color: #c00000;
            position: absolute;
            top: 50%;
            left: 0;
            transform: translateY(-50%);
          }
        }
      }
    }

    // 右侧
    .right-scroll-view {
      .cate-lv2-title {
        font-size: 12px;
        font-weight: bold;
        text-align: center;
        padding: 15px 0;
      }

      .cate-lv3-list {
        display: flex;
        flex-wrap: wrap;

        .cate-lv3-item {
          width: 33.33%;
          display: flex;
          flex-direction: column;
          align-items: center;
          justify-content: center;
          margin-bottom: 10px;

          image {
            width: 60px;
            height: 60px;
          }

          text {
            font-size: 12px;
          }
        }
      }
    }
  }
</style>
